Selection of prefabrication plant is mainly based on type of element to be produced, desired output volume, location at which the plant will operate. These are the major factors deciding the type of prefabrication plant.
In the planning stage of prefabrication plant the following points are to be considered,
- Selection of type of plant:
Permanent field plant or building site plant may be selected.
- Location of the plant site:
It is based on raw material availability, transport facility, availability of labour, availability of power and water, location of marketing area, availability of suitable land, disposal facilities etc.
- Type of production process used:
Stationary mould, Movable mould may be used.
- Finalizing the area required:
Finalizing the area required for storing the raw materials like fine and coarse aggregate, reinforcements, cement, finished elements etc, various sub assemblies to be prepared in plant by using steel bars, rods, and meshes which must be cut, bend, weld, tied before placing inside the mould. Hence sufficient space for auxiliary activities is required.
- In case of movable mould line, if the mechanical failure happened, one mould in the line can affect the fraction of the whole line, hence suitable arrangements are planned to overcome such a problem.
- For withdrawing the malfunctioning the mould or repairing the prefabricated element, the provisions are provided to take it away from the line to avoid interruption of flow of work.
- Business plan preparation is must in planning stage, it should contain the capital requirement, list of customers, money required for land, machinery, buildings, and other infrastructure development, expected time to complete the building construction, machinery installation, other infrastructure work, time to make profit, targeted customer list etc.
- Planning of production type gives the solution to the following type of machinery to be installed, plant layout design, preparation of procedure and systems for operation and management, planning of prefabricated plant before doing a very casual factor in deciding the overall profitability of the project.
The manufacturing cost of a prefabricated element will depend on how well the plant equipment and machinery placed within the site.
For the effective plant layout the following principle factors are to considered.
- Manufacturing cost:
By reducing unwanted material and man work it is possible to reduce the manufacturing cost.
- Process requirements:
The machinery and equipment should be planned to the place the position according to the sequence of operations to be carried out in the prefabricated element.
- Nature of operation:
Important machinery used for frequent operations should be located very conveniently.
- Nature of maintenance:
Some machinery or equipment need frequent dismantling and replacing spares for which simple space should be provided in and around the machine.
Maximum safety to the workers in equipment operation, material handling, rotes of material handling and equipment movement above the workstations should be avoided if it is possible.
- Future expansion:
Layout design in a prefabrication plant should provide convenient working condition for each process and an efficient flow of labour and equipment between the various working areas for the future expansion.
- Adequate space between machineries:
Simple space must be provided between the machineries to reduce the congested working atmospheres to the employees and it helps in maintenance, dismantling works of machineries.
- Adequate space for storage materials.
- Easy access of labour and equipment to all working areas:
Reduce the unwanted wasting time of man and machines. It helps to improve the utilization of man and machine. By designing good plant layout, it is possible to increase profit, productivity, utilization of man and machine and reduces the accidents, manufacturing cost, hence idle time of man and machinery is possible.
- Nearest location for strong fractional relationship activities.
- Providing shortest and most convenient flow of materials within the plant.
- Providing maximum safety to workers.
- Good visual control of work progress.
- Providing simple space for inspection and maintenance work.
- Flexibility for future expansion.
These are the factors to be considered while making the plant layout design.